Thermal sensor

Abstract

To provide a heat sensor with which a translucent member such as an element support member and a top plate can be easily aligned and light, which is transmitted through the translucent member, from a light source is easily visible in a top plate opening.SOLUTION: A heat sensor comprises: a case main body including an opening for storing a substrate on which a sensor for sensing heat and a light source are mounted; a case lid provided at a lower side of the case main body and consisting of a translucent member through which light from the light source is translucent; and a protector including a top plate positioned at a lower side of the case body and a protection part provided in the top plate and protecting the sensor. The case lid includes a hole part through which the sensor is inserted, and the hole part includes a cylindrical portion extending downward. A top plate opening, in which the cylindrical portion is disposed, is provided in the top plate and the cylindrical portion is formed with such a height as to be flush with a bottom face of the top plate.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] The present disclosure relates to a heat detector that includes a light source. [Background technology]

[0002] Conventionally, a heat detector includes a sensor such as a thermistor that detects heat, and detects the occurrence of a fire by detecting the heat of hot air currents generated by a fire. In the heat detector, a board is disposed inside the case body, and a sensor is attached to the board so that a heat-sensing part is exposed through an opening provided on the bottom surface of the case body. Some such heat detectors include a light source mounted on the board, and the light source is turned on when a fire occurs (see, for example, Patent Document 1). The heat detector of Patent Document 1 includes an element support member that is attached to the board and guides light from the light source, and a body cover (top plate) that is disposed below the case body that houses the board and the element support. The heat-sensing part of the sensor protrudes downward from a top plate opening provided in the top plate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-111298 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the heat detector of Patent Document 1, the element support member that guides the light is attached to a substrate and is entirely housed in the case body, and is located above the body cover (top plate). Therefore, when assembling the body cover, it is difficult for an operator to visually recognize the positioning portion of the element support member, making it difficult to perform positioning, and there are also problems with poor visibility of the light when the heat detector is in operation.

[0005] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a heat detector in which the positioning of a translucent member such as an element support member and the top plate can be easily performed, and in which light from a light source that has passed through the translucent member can be easily seen at the opening in the top plate. [Means for solving the problem]

[0006] The heat detector of the present disclosure is a heat detector comprising: a case body having an opening for housing a board on which a heat-sensing sensor and a light source are mounted; a case lid provided below the case body and made of a translucent material that transmits light from the light source; a top plate located below the case lid; and a protector provided on the top plate and having a protective portion for protecting the sensor, wherein the case lid has a hole through which the sensor is inserted, the hole having a cylindrical portion extending downward, the top plate is provided with a top plate opening in which the cylindrical portion is positioned, and the cylindrical portion is formed at a height that is flush with the underside of the top plate.

[0007] In addition, in the above heat detector, the hole has a mortar-shaped portion whose opening width gradually increases toward the bottom, and the cylindrical portion extends downward from the lower end of the mortar-shaped portion, and the case lid has a frame portion extending from the lower end of the mortar-shaped portion toward the outer periphery.

[0008] In addition, in the above heat detector, a first step portion whose outer diameter becomes larger on the upper side is provided on the outer peripheral surface of the cylindrical portion, and a second step portion opposite to the first step portion is provided on the upper surface of the top plate.

[0009] In the above heat detector, the case lid has a plurality of legs extending upward along the inner surface of the case body.

[0010] In addition, in the above heat detector, one end of the wiring that is pulled out to the outside is connected to the substrate, a notch is formed on the edge of the opening of the case body in which the wiring is arranged, a notch is formed on the edge of the substrate, and a protrusion that is placed in the notch of the substrate and extends in the vertical direction on the inner wall of the case body.

[0011] In addition, in the above heat detector, a pair of hooks are provided on the top plate of the protector, extending upward and having folded portions at their tips that face outward toward each other, the inner angle of the folded portion is an acute angle, and the case body is formed with holes into which each of the pair of hooks fits. Effect of the Invention

[0012] According to the present disclosure, the tubular portion in the hole of the case lid, which is made of a translucent material, is positioned in the top plate opening of the top plate and is flush with the underside of the top plate. Therefore, when the main body cover is assembled, the tubular portion can be seen from the top plate opening, making alignment easy, and when the heat detector is operating, the light from the light source that passes through the hole in the case lid can be easily seen at the top plate opening. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is a bottom view of the heat detector according to the first embodiment. [Diagram 2] FIG. 1 is an exploded perspective view showing a configuration of a heat detector according to a first embodiment. [Diagram 3] FIG. 2 is a schematic diagram showing the heat detector of FIG. 1 installed on a ceiling. [Figure 4] FIG. 3 is a plan view of a protector of the heat detector of FIG. 2. [Diagram 5] 5 is a cross-sectional view showing the cross section BB of the top plate of the protector in FIG. 4. [Figure 6] FIG. 5 is a front view of the protector of FIG. [Figure 7] FIG. 7 is a side view of the protector of FIG. 6. [Figure 8]2 is a schematic perspective view showing the heat detector of FIG. 1 with a protector removed, viewed obliquely from below. FIG. [Figure 9] FIG. 3 is a perspective view of a case cover of the heat detector of FIG. 2. [Figure 10] FIG. 10 is a side view of the case lid of FIG. [Figure 11] 2 is a cross-sectional view showing the section AA of the heat detector in FIG. 1. [Figure 12] 2 is a schematic perspective view showing the heat detector of FIG. 1 with a protector and a case lid removed, viewed obliquely from below. FIG. [Figure 13] FIG. 13 is a bottom view of the heat detector of FIG. 12. [Figure 14] 9 is a schematic perspective view showing a state in which wiring is connected to the heat detector of FIG. 8, viewed obliquely from below. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Embodiment 1 FIG. 1 is a bottom view of a heat detector 100 according to the first embodiment. FIG. 2 is an exploded perspective view showing the configuration of the heat detector 100 according to the first embodiment. FIG. 3 is a schematic diagram showing the heat detector of FIG. 1 installed on a ceiling. FIG. 4 is a plan view of a protector 60 of the heat detector 100 of FIG. 2. FIG. 5 is a cross-sectional view showing a BB cross section of the top plate of the protector of FIG. 4. FIG. 6 is a front view of the protector 60 of FIG. 4. FIG. 7 is a side view of the protector 60 of FIG. 6. The schematic configuration of the heat detector 100 will be described below with reference to FIGS. 1 to 3, and the detailed configuration of the protector 60 will be described with reference to FIGS. 1 to 7.

[0015] 1 is installed in a monitored space in a building, for example, and monitors the surrounding temperature. When the surrounding temperature reaches or exceeds a certain temperature, the heat detector 100 outputs a signal to a fire receiver (not shown) indicating that there is a fire.

[0016] As shown in FIG. 2, the heat detector 100 includes a case body 10 having an opening 11, a substrate 20, a sensor 40 for detecting heat, a light source 50 for emitting light, a case lid 30 placed in the opening 11 of the case body 10, and a protector 60 for protecting the sensor 40.

[0017] The substrate 20 is housed in the case body 10 through the opening 11. Various electronic components including a sensor 40 and a light source 50 are mounted on the substrate 20. The case lid 30 is detachably attached to the case body 10 in which the substrate 20 is housed. The case lid 30 is provided so as to cover the entire or part of the opening of the case body 10. A first hole 31 through which the sensor 40 is inserted is formed in the center of the case lid 30. The protector 60 is provided to protect the tip of the sensor 40 that protrudes in the heat detector 100. The protector 60 is formed with a second hole 69 through which airflow passes. The second hole 69 will be described later. The first hole 31 of the case lid 30 is exposed from a top plate opening 64a provided in the center of a top plate 64 of the protector 60, which will be described later. Here, the first hole 31 refers to the entire wall surrounding the hole through which the sensor 40 is inserted.

[0018] 3, the heat detector 100 is installed in a recess 202 in, for example, a ceiling 200 formed on the opposite side to the monitored space. Specifically, the case body 10 is accommodated in the recess 202 of the ceiling 200, and the heat detector 100 is installed on the ceiling 200 so that the protector 60 protrudes from the ceiling surface 201 into the monitored space.

[0019] In each drawing, the arrow Z direction is described as representing the height direction (up-down direction) of the heat detector 100 when it is installed on the ceiling 200. That is, in a state where the heat detector 100 is installed on the ceiling 200 as shown in FIG. 3, the side closer to the floor is defined as the bottom. A protector 60 is attached under the case body 10. In a state where the heat detector 100 is installed on the ceiling 200, the case body 10 constituting the upper outer surface of the heat detector 100 faces the inner surface of the recess 202 of the ceiling 200, and the protector 60 constituting the lower outer surface of the heat detector 100 is exposed to the room, which is the monitored space. In addition, the arrow X direction in each drawing is defined as representing the width direction (left-right direction) of the heat detector 100, and the arrow Y direction is defined as representing the depth direction (front-back direction) of the heat detector 100.

[0020] As shown in Fig. 2, the opening 11 of the case body 10 is formed on the underside of the case body 10. In the example shown in Fig. 2, the case body 10 has a box shape with an open bottom. The case lid 30 is provided on the underside of the case body 10, i.e., on the opening side.

[0021] (Configuration of Protector 60) As shown in FIG. 2, the protector 60 is disposed below the case lid 30. The protector 60 has a protective plate 62 disposed below the case lid 30 so as to face the first hole portion 31 of the case lid 30, a top plate 64 disposed above the protective plate 62, and a plurality of supports 63 supporting the protective plate 62. As shown in FIG. 3, the top plate 64 is attached to the case body 10 and disposed below the case body 10 so as to cover the recess 202 of the ceiling 200 when the heat detector 100 is installed on the ceiling 200. The plurality of supports 63 connect the protective plate 62 and the top plate 64. The plurality of supports 63 and the protective plate 62 constitute a protective section 61 that protects the sensor 40 and the heat-sensing section 41, which is the tip of the sensor 40, from external factors such as fingers.

[0022] 2 and 4, a top plate opening 64a is formed in the center of the top plate 64. As shown in Fig. 2, the top plate 64 has a disk shape. The sensor 40 protruding from the case body 10 is inserted into the top plate opening 64a via a first hole 31 provided in the center of the case lid 30. The lower part of the first hole 31 is disposed in the top plate opening 64a.

[0023] 5, a second step 64r is formed on the inner wall of the top plate opening 64a of the top plate 64 on the upper surface 64s1 side, and the top plate opening 64a is formed so that the opening width Di2a at the upper part is larger than the opening width Di2b at the lower part. A first step 32p of the case lid 30 shown in FIG. 8, which will be described later, is disposed on the second step 64r of the top plate 64.

[0024] 4, 6 and 7, a plurality of hooks 65a, 65b, 65c and 65d are provided on the top plate 64 of the protector 60, and the protector 60 is attached to the case body 10 (see FIG. 3) by the hooks 65a to 65d. The plurality of hooks 65a to 65d are provided so as to extend upward from the upper surface 64s1 of the top plate 64, and a folded portion 65a1, 65b1, 65c1 or 65d1 folded back outward is formed at the tip of each of the hooks 65a, 65b, 65c or 65d. Furthermore, as shown in FIG. 4, a plurality of positioning recesses 66 are formed on the upper surface 64s1 of the top plate 64 of the protector 60. When the protector 60 is attached to the case body 10 (see FIG. 3) using the hooks 65a to 65d, the positioning protrusion 17 formed on the case body 10 shown in FIG. 8 described later is inserted into the positioning recess 66 of the top plate 64, thereby positioning the case body 10 and the protector 60.

[0025] In the example shown in FIG. 4, the protector 60 has two pairs of hooks provided on both sides of the top plate opening 64a. In each of the pair of left-right hooks consisting of the left hook 65a and the right hook 65b, and the pair of front-rear hooks consisting of the front hook 65c and the back hook 65d, the folded back portions of the two opposing hooks face outward from each other. As shown in FIG. 6, in the pair of left-right hooks (arrow X direction), the interior angle θ1 of the folded back portions 65a1 and 65b1 of the two hooks 65a and 65b is approximately a right angle. Specifically, the interior angle θ1 is a right angle (i.e., 90°) or an obtuse angle slightly larger than 90° (for example, an obtuse angle larger than 90° and not larger than 92°). On the other hand, as shown in FIG. 7, in a pair of hooks in the front-rear direction (arrow Y direction), the inner angle θ2 between the folded-back portions 65c1 and 65d1 of the two hooks 65c and 65d is an acute angle.

[0026] The number of pairs of hooks provided on the top plate 64 is not limited to two. The number of pairs of hooks may be, for example, one pair or three or more pairs. The number of hooks provided on the top plate 64 may be appropriately determined according to the shape of the case body 10, and may be an odd number of three or more. In the example shown in FIG. 4, FIG. 6, and FIG. 7, the inner angle θ2 of the folded parts 65c1 and 65d1 in the pair of hooks in the front-rear direction is an acute angle, but the inner angle θ1 of the folded parts 65a1 and 65b1 in the pair of hooks in the left-right direction may be an acute angle. In addition, when the number of pairs of hooks is two or more, it is sufficient that the inner angle of the folded parts of the opposing hooks in at least one pair is an acute angle.

[0027] As shown in Fig. 7, by making the inner angle θ2 of the folded-back portions 65c1 and 65d1 in the pair of hooks an acute angle, when the folded-back portions 65c1 and 65d1 are inserted into the hook holes 14c and 14d of the case body 10 shown in Fig. 12 described later, they are caught by the edges. Therefore, the protector 60 attached to the case body 10 as shown in Fig. 3 is prevented from coming off from the case body 10.

[0028] As shown in FIG. 2, the top plate 64 of the protector 60 is provided with two springs 67 extending from the surface (upper surface 64s1 shown in FIG. 4) on the side of the case body 10 toward the outer periphery. In the example shown in FIG. 2, the band-shaped springs 67 extending outward are provided at the front and rear edges of the upper surface 64s1 of the top plate 64. As shown in FIG. 3, when the case body 10 is accommodated in the recess 202 of the ceiling 200, the two springs 67 provided on the top plate 64 of the protector 60 press the left and right inner surfaces of the recess 202, so that the top plate 64 is held by the recess 202 of the ceiling 200. Therefore, the top plate 64 and the case body 10 attached to the top plate 64 are prevented from falling out of the recess 202 of the ceiling 200.

[0029] The shape of the spring is not particularly limited to this. The mounting configuration of the heat detector 100 to the ceiling 200 is also not limited to this. As shown in Fig. 1 and Fig. 3, the outer diameter Do2 of the top plate 64 is set to a dimension larger than the maximum width of the case body 10, and the case body 10 and the recess 202 of the ceiling 200 are configured to be invisible to the user.

[0030] As shown in FIG. 1 and FIG. 2, a protective plate opening 62o is formed in the center of the protective plate 62, and the protective plate 62 has a disk shape. The outer diameter Do1, the inner diameter (opening width Di1 of the protective plate opening 62o), or the difference between the outer diameter Do1 and the inner diameter (opening width Di1) of the protective plate 62 shown in FIG. 1 are determined so that the first hole 31 of the case lid 30 can be seen through the second hole 69 of the protector 60 (see FIG. 2) when the user looks at the heat detector 100 at a predetermined elevation angle. Note that it is sufficient that the first hole 31 can be seen by the user through at least one of the protective plate opening 62o and the gap 63g between the multiple supports 63 shown in FIG. 2. Here, the predetermined elevation angle is an angle at which the user looks up at the heat detector 100, and may be an angle at which a user located 15 meters away from the heat detector 100 looks up at the heat detector 100 installed at a height of 3 meters from the floor. The inner diameter of the protective plate 62, that is, the opening width of the protective plate opening 62o, is preferably set to a dimension that can prevent a test finger or the like from entering and touching the heat sensitive portion 41 (for example, 8 mm or less).

[0031] In a plan view of the protector 60 shown in Fig. 4, the center of the protective plate opening 62o of the protective plate 62 and the center of the top plate opening 64a of the top plate 64 are located on a straight line extending in the vertical direction (the direction of the arrow Z shown in Fig. 3). In a bottom view of the heat detector 100 as shown in Fig. 1, the center of the protective plate opening 62o of the protective plate 62, the center of the top plate opening 64a (see Fig. 4) of the top plate 64, and the center of the first hole 31 of the case lid 30 are located on a straight line extending in the vertical direction (the direction of the arrow Z shown in Fig. 3). The sensor 40 is disposed along this straight line.

[0032] As shown in Fig. 4, the inner diameter of the protective plate 62, i.e., the opening width Di1 of the protective plate opening 62o, is preferably set to a dimension equal to or smaller than the inner diameter of the top plate 64, i.e., the opening width Di2b of the lower part of the top plate opening 64a. As shown in Fig. 1, the opening width Di1 of the protective plate opening 62o and the opening width Di2b of the top plate opening 64a shown in Fig. 4 are both larger than the diameter of the tip of the sensor 40 to be inserted (the diameter of the heat-sensing part 41 shown in Fig. 2), and are preferably set to a dimension larger than the inner diameter of the case lid 30, i.e., the minimum opening width Di0 of the first hole 31. With this configuration, in a bottom view of the heat detector 100 as shown in Fig. 1, a portion of the case lid 30 located inside the protector 60, specifically, the inner wall portion of the first hole 31, can be seen from the outside of the heat detector 100 through the protective plate opening 62o of the protector 60.

[0033] As shown in FIG. 2, FIG. 3, FIG. 6, and FIG. 7, the support 63 of the protector 60 is made of, for example, a plate-shaped member, and the multiple support 63 are arranged radially with a gap 63g between adjacent support 63. The gap 63g is preferably set to a dimension (for example, 8 mm or less) that can prevent a test finger or the like from entering. The support 63 is made of, for example, an opaque member. As shown in FIG. 6 and FIG. 7, each support 63 extends downward from the periphery of the top plate opening 64a on the lower surface 64s2 of the top plate 64 and is connected to the periphery of the protective plate opening 62o (see FIG. 4) on the upper surface of the protective plate 62. The outer diameter Do1 of the protective plate 62 is set to a dimension larger than the outer diameter Do3 formed by the multiple support 63 arranged radially. With this configuration, the multiple support 63 of the heat detector 100 can be made difficult to see from a user viewing from below, so that the aesthetic appearance can be improved and the design can be improved.

[0034] As shown in FIG. 3, an airflow circulation space SP is formed in the protector 60 by the protective plate 62, the multiple support columns 63, and the top plate 64 of the protector 60, and the first hole portion 31 (see FIG. 2) of the case lid 30. When the heat detector 100 is installed on the ceiling 200, a vertical airflow flows into the circulation space SP through the protective plate opening 62o (see FIG. 2). Here, the vertical airflow refers to an airflow that flows in a direction perpendicular to the ceiling surface 201. In addition, a horizontal airflow flows into the circulation space SP through the gap 63g formed between the support columns 63, and the airflow in the circulation space SP flows out to the outside of the heat detector 100. Here, the horizontal airflow refers to an airflow that flows in a direction parallel to the ceiling surface 201. That is, as shown in FIG. 2, the protective plate opening 62o provided in the protective plate 62 and the gaps 63g between the plurality of posts 63 each function as a second hole portion 69 through which air current passes in the protector 60.

[0035] The configuration of the protector 60 is not limited to the above configuration. The configuration in which the first hole 31 of the case lid 30 is visible through the second hole 69 of the protector 60 when the user looks at the heat detector 100 at a predetermined elevation angle has been described with reference to Fig. 2, but for example, by making the thickness of the support pillars 63 thicker or increasing the number of support pillars 63 within a range that does not affect the heat reception of the sensor 40, a configuration in which the sensor 40 is difficult to see from the user through the gap 63g but the light can be seen.

[0036] FIG. 8 is a schematic perspective view showing the heat detector 100 of FIG. 1 with the protector 60 removed, viewed from a diagonal downward direction. FIG. 9 is a perspective view of the case lid 30 of the heat detector 100 of FIG. 2. FIG. 10 is a side view of the case lid 30 of FIG. 9. FIG. 11 is a cross-sectional view showing the AA section of the heat detector 100 of FIG. 1. FIG. 12 is a schematic perspective view showing the heat detector 100 of FIG. 1 with the protector 60 and the case lid 30 removed, viewed from a diagonal downward direction. FIG. 13 is a bottom view of the heat detector 100 of FIG. 12. FIG. 14 is a schematic perspective view showing the heat detector 100 of FIG. 8 with wiring connected, viewed from a diagonal downward direction. Hereinafter, the structures of the case lid 30, the substrate 20, the sensor 40, the light source 50, and the case main body 10 will be described in detail with reference to FIGS. 1 to 14.

[0037] (Configuration of case lid 30) As shown in Fig. 8 to Fig. 11, the opening of the first hole 31 formed in the center of the case lid 30 has an opening width equal to or larger than the diameter of the heat-sensing part 41 of the sensor 40 protruding from the case lid 30 so that the sensor 40 can be inserted when assembling the heat detector 100. The case lid 30 has a frame part 34 extending from the outer circumferential surface 32o of the first hole 31 toward the outer circumferential side, and is configured to cover a part of the lower surface 21 of the substrate 20 with the frame part 34 while exposing the heat-sensing part 41 of the sensor 40 to the outside from the opening of the first hole 31. As shown in Fig. 11, in the first hole 31 formed in the center of the case lid 30, the inner circumferential surface facing the lead part 42 of the sensor 40 and the lower end 31b are exposed to the flow space SP in the case lid 30.

[0038] 8, the frame portion 34 has a rectangular planar shape, and the first hole portion 31 is formed in the center of the frame portion 34. Note that the frame portion 34 and the first hole portion 31 may be formed of separate members in the case lid 30. In addition, the shape of the frame portion 34 is not limited to a rectangular shape.

[0039] The case lid 30 is made of a light-transmitting member. As shown in Figs. 8 to 11, the first hole 31 has a mortar-shaped portion 33 whose opening width gradually increases downward, and a tubular portion 32 extending downward from a lower end 33b of the mortar-shaped portion 33. In the example shown in Fig. 11, the wall of the mortar-shaped portion 33 is inclined, so that the upper end surface 31a of the wall is inclined from the horizontal direction. Therefore, in the example shown in Fig. 11, to be precise, the upper end portion of the mortar-shaped portion 33 has a shape in which the opening width gradually decreases downward, and the portion of the mortar-shaped portion 33 below the upper end portion has a shape in which the opening width gradually increases downward. In this configuration, it is easy to pass the sensor 40 through the first hole 31 when attaching the case lid 30 to the case body 10.

[0040] 11, the opening width of the cone-shaped portion 33 on the light source 50 side, i.e., at the upper end (i.e., the minimum opening width Di0 of the first hole portion 31) is larger than the thickness of the tip of the sensor 40 and is the same as or smaller than the opening width Di1 of the protective plate opening 62o of the protector 60. The lower end of the tubular portion 32 is the lower end 31b of the first hole portion 31. In the example shown in FIG. 11, the tubular portion 32 has a cylindrical shape with a constant opening width Di32 from the upper end connected to the lower end 33b of the cone-shaped portion 33 to the lower end 31b.

[0041] 11, the cylindrical portion 32 of the first hole portion 31 is provided so as to protrude downward from the frame portion 34, and is disposed in a top plate opening 64a provided in the top plate 64. The cylindrical portion 32 is formed to a height H such that the surface of the lower end 31b of the cylindrical portion 32 is flush with the lower surface 64s2 of the top plate 64. In the example shown in FIG. 11, the cylindrical portion 32 has a height H that is approximately the same as the thickness T of the top plate 64 of the protector 60, and is configured so that the entire cylindrical portion 32 is inserted into the top plate opening 64a of the top plate 64 in the up-down direction (arrow Z direction). In this manner, the cylindrical portion 32 of the first hole portion 31 is disposed in the top plate opening 64a provided in the top plate 64 through which the sensor 40 passes, and the surface of the lower end 31b of the cylindrical portion 32 is exposed from the lower surface 64s2 of the top plate 64, so that most of the cylindrical portion 32 can be easily viewed by an operator through the top plate opening 64a provided in the center of the top plate 64 when assembling the heat detector 100. This makes it easy to align the case lid 30 and the protector 60.

[0042] As shown in Figs. 8 to 11, a first step 32p is provided on the outer peripheral surface 32o of the cylindrical portion 32. In the example shown in Fig. 10, the first step 32p is formed at the upper end of the outer peripheral surface 32o of the cylindrical portion 32 so as to protrude toward the outer peripheral side. The cylindrical portion 32 is configured so that the outer diameter D32a on the frame portion 34 side on which the first step 32p is provided is larger than the outer diameter D32b of the lower portion. As shown in Fig. 11, the top plate 64 of the protector 60 is disposed below the frame portion 34 of the case lid 30 so that the first step 32p provided on the outer peripheral surface 32o of the cylindrical portion 32 faces the second step 64r provided on the upper surface 64s1 of the top plate 64.

[0043] The shape and position of the first step 32p are not limited to the illustrated embodiment as long as the first step 32p is shaped and positioned to engage with the second step 64r of the top plate 64. Specifically, the first step 32p may be provided so as to protrude or recess on the surface of the case lid 30 facing the top plate 64 of the protector 60. The first step 32p may be provided, for example, on the lower surface of the frame 34 of the case lid 30 so as to protrude downward.

[0044] When the case lid 30 and the top plate 64 are aligned in the vertical direction, the first step 32p and the second step 64r engage with each other, thereby roughly aligning the case lid 30 and the protector 60 in a direction parallel to the top plate 64, i.e., in the horizontal direction. The final positioning of the case lid 30 and the protector 60 is determined by fixing the protector 60 to the case body 10.

[0045] It is only necessary that the top plate 64 and the first hole 31 are arranged so that the space inside the case body 10 is not directly visible to the user. Therefore, the first step 32p of the case lid 30 and the second step 64r of the protector 60 need not be fitted together as long as the case lid 30 and the protector 60 can be roughly aligned in the horizontal direction. In this case, the protector 60 is fixed to the case lid 30 by attaching it to the case body 10 with a plurality of hooks 65a to 65d.

[0046] 11, the height H of the cylindrical portion 32 is the same as the thickness T of the top plate 64 of the protector 60, but as long as the surface of the lower end 31b of the cylindrical portion 32 is flush with the lower surface 64s2 of the top plate 64, the height H of the cylindrical portion 32 does not have to be the same as the thickness T of the top plate 64. For example, the cylindrical portion 32 may be configured so that only a portion in the vertical direction is inserted into the top plate opening 64a. In this case, the height H of the first step 32p from the lower surface of the frame 34 is made larger than the depth Ds (see FIG. 5) of the second step 64r from the upper surface 64s1 of the top plate 64, so that the surface of the lower end 31b of the cylindrical portion 32 and the lower surface 64s2 of the top plate 64 can be arranged to be flush with each other.

[0047] The configuration of the first hole portion 31 is not limited to the above configuration. For example, the cylindrical portion 32 does not have to be configured to have a constant opening width D32 from its upper end to its lower end 31b. For example, the cylindrical portion 32 may be inclined as long as the inner peripheral surface of the cylindrical portion 32 shown in FIG. 11 is a surface that is more gently inclined than the inner peripheral surface of the mortar-shaped portion 33.

[0048] In the present embodiment, the portion of first hole 31 above cylindrical portion 32 has been described as having a mortar shape, but the shape of the upper portion of first hole 31 is not limited to this. If the opening width at the upper portion of first hole 31 on the cylindrical portion 32 side, i.e., on lower end 33b, is larger than the opening width at the light source 50 side, i.e., on the upper end (i.e., the minimum opening width Di0 of first hole 31), the light emitted from light source 50 can be diffused at the upper portion of first hole 31, and the light emission area can be increased.

[0049] As shown in FIG. 8, the frame 34 is provided so as to extend from the lower end 33b of the mortar-shaped portion 33 to the outer periphery. A plurality of legs 35 are provided on the edge of the frame 34 so as to extend upward from the frame 34, i.e., toward the substrate 20. Also, as shown in FIG. 8 and FIG. 9, a plurality of lid protrusions 34p protruding to the outer periphery are formed on the edge of the frame 34. In the example shown in FIG. 9, the legs 35 extending upward are provided at the four corners of the frame 34, the lid protrusions 34p protruding forward are provided on the front edge of the frame 34, and the lid protrusions 34p protruding backward are provided on the rear edge of the frame 34. Also, as shown in FIG. 9 and FIG. 10, the case lid 30 has a claw portion 34x protruding to the outer periphery at a position above the lid protrusions 34p on the side that contacts the inner surface of the case body 10 (see FIG. 8).

[0050] As shown in FIG. 8, the case lid 30 is attached to the case body 10 such that the legs 35 and the frame 34 are housed in the case body 10 and the first hole 31 protrudes downward from the opening 11 of the case body 10. When the case lid 30 is attached to the case body 10, the case lid 30 is pushed in so that the legs 35 slide along the inner surface of the case body 10. When the case lid 30 is pushed in to a certain depth, the lid protrusion 34p of the frame 34 is positioned in the first cutout 15 formed on the edge of the opening 11 of the case body 10 shown in FIG. 12 to be described later, so that the movement of the case lid 30 stops, and the claw 34x shown in FIG. 9 is engaged with the claw hole 14e of the case body 10 shown in FIG. 12 to be described later, so that the case lid 30 is locked.

[0051] As described above, the case lid 30 can be fixed to the case body 10 with a simple structure such as the claw portions 34x.

[0052] It is not necessary to provide a structure for fixing the case lid 30 to the case body 10. In this case, the structure can be simplified and assembly can be facilitated by configuring the case lid 30 to be fitted into the case body 10 so that the frame 34 of the case lid 30 is sandwiched between the case body 10. The multiple legs 35 function as guides when fitting the case lid 30 into the case body 10.

[0053] The length of the legs 35 is determined so as not to come into contact with the board 20 or various electronic components mounted on the board 20. The length of the legs 35 may be set so that the tips of the legs 35 come into contact with the lower surface 21 of the board 20 housed in the case body 10 when the case lid 30 is installed on the case body 10. In this case, the tips of the legs 35 can press the board 20 upward, suppressing movement of the board 20 within the case body 10.

[0054] As shown in Fig. 8, the size of the frame 34 is smaller than the size of the opening 11 of the case body 10, and gaps are formed on both sides of the frame 34 when the case lid 30 is installed on the case body 10. In the example shown in Fig. 8, the width of the frame 34 in the front-rear direction (arrow Y direction) is formed to be approximately the same as the opening width of the opening 11 in the front-rear direction, and the width of the frame 34 in the left-right direction (arrow X direction) is smaller than the opening width of the opening 11 in the left-right direction, and gaps are formed on the right and left sides of the frame 34. When manufacturing the heat detector 100, the substrate 20 is accommodated in the case body 10, the case lid 30 is installed, and then a filler is injected into the case body 10 through the gaps. The filler will be described later.

[0055] The size of the frame 34 is not limited to the above. For example, the size of the frame 34 may be the same as the size of the opening 11, and an injection port may be provided in the frame 34. In addition, when the size of the frame 34 is the same as the size of the opening 11, the filler may be injected through the first hole 31.

[0056] 8, in the case lid 30, a groove 34c in which the hooks 65c and 65d of the protector 60 are disposed is formed on the side surface that contacts the inner surface of the case body 10. Specifically, as shown in FIG 9, the groove 34c is formed in the frame portion 34 and the leg portion 35 so as to extend in the up-down direction (the direction of the arrow Z).

[0057] In the example shown in Fig. 8, grooves 34c are formed on the front and rear side surfaces of the case lid 30, and a pair of hooks 65c and 65d shown in Fig. 4 and 6 are attached to the case body 10 through the grooves 34c. In the example shown in Fig. 8, gaps are formed on the left and right sides of the frame portion 34 in the opening 11, and a pair of hooks 65a and 65b shown in Fig. 4 and 7 are attached to the case body 10 through the gaps.

[0058] (Substrate 20) 2 and 13, the board 20 is, for example, a polygonal printed circuit board. In the example shown in Fig. 2, the board 20 is shaped like an elongated bundle having long sides extending in the left-right direction (the direction of the arrow X), and is disposed in the case body 10 so that both sides of the board 20 face upward and downward. Various electronic components are mounted on the board 20 to form a control circuit.

[0059] The arrangement of the substrate 20 is not limited to the above. The substrate 20 may be placed vertically inside the case body 10. For example, the substrate 20 may be substantially rectangular with long sides extending in the vertical direction (arrow Z direction) and may be placed inside the case body 10 so that both surfaces of the substrate 20 face forward and backward.

[0060] As shown in FIGS. 2, 8 and 12, the light source 50 and the sensor 40 are attached to the lower surface 21 of the substrate 20 at predetermined positions by soldering.

[0061] 13, the substrate 20 is provided with a wiring connection portion 26, and one end of a wiring 27 shown in Fig. 14 is connected to the wiring connection portion 26. The other end of the wiring 27 connected to the substrate 20 is drawn out to the outside of the case body 10.

[0062] Also, a notch 23 is formed on an edge of the substrate 20. As shown in Fig. 12 and Fig. 13, a guide protrusion 13 provided on the inner wall of the case body 10 is disposed in this notch 23. The configuration of the guide protrusion 13 will be described later. As shown in Fig. 13, the notch 23 is provided at a position eccentric from the center of the longitudinal side of the substrate 20. In the example shown in Fig. 13, the notch 23 is formed on each of the front and rear edges, which are the long sides of the substrate 20, at a position to the left of the center in the left-right direction (arrow X direction).

[0063] A control circuit formed on the substrate 20 receives the output value of the sensor 40 and determines the ambient temperature based on the output value. When the control circuit determines that the ambient temperature is equal to or higher than a certain temperature, the control circuit transmits a fire signal to a receiver (not shown) and controls the light source 50 to light up or blink.

[0064] (Sensor 40) 11, the sensor 40 has a heat-sensing unit 41 that detects heat, and detects the heat of the airflow that has flowed into the circulation space SP. The heat-sensing unit 41 is composed of, for example, a thermistor or the like whose resistance changes depending on the heat transmitted from the airflow, and converts the temperature change into an electrical signal for output.

[0065] The sensor 40 is composed of, for example, a heat-sensing part 41, a rod-shaped lead part 42 made of a lead wire, a sensor base 44 having two pins (not shown) attached to the substrate 20, and a connection part 43 connecting the lead part 42 and the sensor base 44. The heat-sensing part 41 is attached to the tip part of the lead part 42, and the heat-sensing part 41 and the lead part 42 are integrally coated. The connection part 43 connects the base end of the lead part 42 to the tip parts of the two pins of the sensor base 44, and is covered with resin or the like. The two pins of the sensor base 44 are fixed to the substrate 20 by soldering, and the heat-sensing part 41 is electrically connected to the control circuit of the substrate 20.

[0066] In order to detect the heat of the vertical airflow, the heat-sensing unit 41 is disposed in the flow space SP directly above the center of the protective plate opening 62o of the protector 60. Specifically, the heat-sensing unit 41 is disposed at a preset position in the flow space SP by the sensor base 44 and the lead portion 42 connected to the sensor base 44. In the example shown in Fig. 11, the sensor 40 is disposed in the vertical direction (direction of arrow Z) perpendicular to the substrate 20 disposed horizontally inside the case body 10.

[0067] (light source 50) The light source 50 is composed of, for example, an LED (Light Emitting Diode) or the like. As shown in Fig. 11, the light source 50 is soldered to the lower surface 21 of the substrate 20 at an upper portion thereof so that the light emitting surface 51 faces downward. The light source 50 is preferably mounted on the lower surface 21 of the substrate 20 at a position above the first hole portion 31 of the case lid 30. By providing the light source 50 in this manner, it is possible to prevent the light emitted from the light source 50 from being blocked by electronic components other than the light source 50 mounted on the substrate 20 before it reaches the first hole portion 31.

[0068] In the example shown in FIG. 13, two light sources 50 are mounted on the substrate 20, one of the light sources 50 is disposed in front of the sensor 40, and the other light source 50 is disposed behind the sensor 40. In the bottom view of FIG. 13, the two light sources 50 are disposed so that the centers of the two light-emitting surfaces 51 in the front-rear direction (arrow Y direction) coincide with the center position of the sensor 40. The distance K between the two light sources 50 shown in FIG. 13 is preferably equal to or less than the inner diameter of the top plate 64 of the protector 60 shown in FIG. 5, that is, the lower opening width Di2b of the top plate opening 64a. In this case, the light of each light source 50 is less likely to be blocked by the top plate opening 64a, and is easier to see. In this case, it is preferable that the distance K between the two light sources 50 is longer than the minimum opening width Di0 of the first hole portion 31 shown in FIG. 1. In this case, it is possible to prevent the light emitted by the light source 50, which is particularly intense and directed downward, from being emitted directly through the gap between the first hole portion 31 and the sensor 40, and also to allow the intense downward light to enter the translucent material of the case lid 30 and be diffused, thereby reducing the directionality of the light.

[0069] The number of light sources 50 and the arrangement of the light sources 50 are not limited to the above. For example, two light sources 50 may be arranged in the left-right direction (the direction of the arrow X).

[0070] Also, the distance K between the two light sources 50 in the front-back direction (arrow Y direction) shown in Fig. 13 may be further increased to a dimension larger than the opening width Di1 of the protective plate opening 62o shown in Fig. 4. This allows the locally bright portion directly below the light source 50 (see Fig. 8) in the first hole portion 31 shown in Fig. 1 to be covered by the protective plate 62, thereby reducing glare.

[0071] 11, in order to allow the light emitted by the light source 50 provided on the underside 21 of the substrate 20 to enter the entire first hole 31 of the case lid 30, the distance between the underside of the substrate 20 and the frame 34 of the case lid 30 may be adjusted based on the directional characteristics of the light of the light source 50. In order to allow the light to enter the first hole 31 of the case lid 30 over as wide an area as possible, the distance between the underside of the substrate 20 and the frame 34 of the case lid 30 may be increased.

[0072] (Case body 10) As shown in Fig. 12, the case body 10 has a case outer shell 12 having a box shape with an open bottom. When the heat detector 100 is installed on the ceiling 200 as shown in Fig. 11, the outer surface of the case outer shell 12 faces the inner surface of the recess 202 of the ceiling 200.

[0073] 12, the inner wall of the case outer shell 12 is provided with a guide protrusion 13 that is disposed in the notch 23 of the substrate 20. The guide protrusion 13 is provided on the inner wall of the case main body 10 at a position facing the notch 23 provided in the substrate 20. In the example shown in FIG. 13, the guide protrusion 13 is formed at a position shifted to the left from the center in the left-right direction (arrow X direction) on the front and rear edges extending in the longitudinal direction of the case main body 10. In this way, by providing the guide protrusion 13 corresponding to the notch 23 of the substrate 20 on the inner wall of the case main body 10, it is possible to prevent the substrate 20 from being inserted in the wrong direction during assembly.

[0074] The number and positions of the notches 23 of the substrate 20 and the guide protrusions 13 of the case body 10 are not limited to the above. For example, the notches 23 of the substrate 20 and the guide protrusions 13 of the case body 10 may be provided in only one location. Even in this case, it is possible to prevent the substrate 20 from being inserted in the wrong direction during assembly.

[0075] 12, the guide protrusion 13 is provided to extend in the vertical direction (arrow Z direction) on the inner wall of the case body 10. By making the guide protrusion 13 extend in the vertical direction, the guide protrusion 13 functions as a guide for the board 20 when the board 20 is accommodated in the case body 10 during assembly.

[0076] 12 and 13, a first cutout portion 15 is formed on the edge of the opening 11 of the case body 10. A lid protrusion portion 34p provided on the frame portion 34 of the case lid 30 is disposed in the first cutout portion 15. In the example shown in Figs. 12 and 13, the first cutout portion 15 is formed in the front and rear side walls of the case body 10 in portions facing the frame portion 34 (see Fig. 8).

[0077] As shown in Fig. 12, the case body 10 has claw holes 14e into which the claw portions 34x shown in Fig. 9 are hooked. In the example shown in Fig. 12, the claw holes 14e are formed in the front and rear side walls of the case body 10 in portions facing the claw portions 34x (see Fig. 9), i.e., at positions above the first cutout portions 15.

[0078] 13 and 14, second cutouts 16 are formed on the edge of the opening 11 of the case body 10. Part of the wiring 27 connected to the substrate 20 and drawn out is disposed in the second cutouts 16. In the example shown in FIG. 13, the wiring connection parts 26 are provided at three of the four corners of the substrate 20, and three second cutouts 16 are formed on the edge of the opening 11 so that the path of the wiring 27 connected to the wiring connection parts 26 within the case body 10 is the shortest. Specifically, the second cutouts 16 are formed at the left end of the front side wall of the case body 10 and at the left and right ends of the rear side wall of the case body 10.

[0079] 14, the provision of the second cutout portion 16 makes it easy to pull out the wiring 27. Furthermore, by providing the second cutout portion 16, even after the board 20 to which the wiring 27 is connected is housed in the case body 10, the movement of the wiring 27 is suppressed by arranging the wiring 27 in the second cutout portion 16, so that subsequent assembly work becomes easier.

[0080] 8 and 12, a positioning protrusion 17 protruding downward is formed on the edge of the opening 11 of the case body 10. In the example shown in Fig. 8, the positioning protrusions 17 are provided at two locations, one at the front and one at the back, on the lower surfaces of each of the left and right side walls of the case body 10. The positioning protrusions 17 of the case body 10 shown in Fig. 8 are inserted into the positioning recesses 66 (see Fig. 4) on the upper surface 64s1 of the top plate 64 shown in Fig. 4, thereby positioning the case body 10 and the protector 60, and as a result, the positional relationship between the case lid 30 attached to the case body 10 and the protector 60 is also determined.

[0081] 12, the case body 10 has hook holes 14a, 14b, 14c, and 14d into which the folded portions 65a1, 65b1, 65c1, and 65d1 of the hooks 65a to 65d of the protector 60 shown in FIGS. 4, 6, and 7 are inserted. The folded portions 65a1 and 65b1 of the hooks 65a and 65b shown in FIG. 6 are inserted into the hook holes 14a and 14b provided in the left and right side walls of the case body 10, and hooked onto the case outer shell 12. The folded portions 65c1 and 65d1 of the hooks 65c and 65d shown in FIG. 7 are inserted into the hook holes 14c and 14d provided in the front and rear side walls of the case body 10.

[0082] The outwardly folded-back portions 65a1, 65b1, 65c1, and 65d1 provided at the tips of the hooks 65a, 65b, 65c, and 65d shown in Fig. 6 and Fig. 7 are supported by contacting the lower inner surface of the hook holes 14a, 14b, 14c, and 14d of the case body 10 shown in Fig. 12, so that the protector 60 does not fall off from the case body 10 even if the protector 60 is subjected to its own weight. In particular, in a pair of hooks 65c, 65d facing each other in the front-rear direction (arrow Y direction) as shown in Fig. 7, the folded-back portions 65c1 and 65d1 are configured to face outward from each other and the inner angle θ2 of the folded-back portions 65c1 and 65d1 is an acute angle, so that the folded-back portions 65c1 and 65d1 fit into the lower edges of the hook holes 14c and 14d in the case outer shell 12 shown in Fig. 12. This makes it possible to more reliably prevent the protector 60 from coming off the case body 10.

[0083] Although not shown, the space in the case body 10 is filled with a filler when the heat detector 100 is manufactured, and the board 20 on which various electronic components are mounted, the case body 10, and the case lid 30 are fixed together by the hardening of the filler. The board 20 is also waterproofed by the hardening of the filler. For the filler, a transparent or translucent light-transmitting material such as polyurethane is used. The filler is preferably provided so that the light source 50 mounted on the board 20 is covered by the filler. This allows the light emitted by the light source 50 to be diffused in the filler, and the light can be prevented from being concentrated and incident locally in the first hole portion 31 of the case lid 30. The filler can be omitted.

[0084] Next, the operation of the heat detector 100 will be described with reference to Fig. 1 and Fig. 11. When a hot air current generated during a fire passes through the center of the circulation space SP shown in Fig. 11, heat is transferred from the hot air current to the heat-sensing part 41. The light emitted by the light source 50 is emitted into the circulation space SP in the protector 60 through the circular first hole 31 formed in the center of the case lid 30. The light from the light source 50 first enters the mortar-shaped part 33 in the first hole 31 and is diffused in the mortar-shaped part 33. After being diffused in the mortar-shaped part 33, the light from the light source 50 enters the tubular part 32 from the lower end 33b of the mortar-shaped part 33 and is guided downward. The light diffused in the first hole 31, guided downward, and emitted into the circulation space SP in the protector 60 illuminates the part of the protector 60 facing the circulation space SP. The light emitted into the flow space SP is emitted to the outside of the heat detector 100 through a circular protective plate opening 62o formed in the center of the protective plate 62 of the protector 60 and through gaps 63g between a plurality of supports 63 arranged radially on the side surface of the protector 60. As light is emitted from the center of the heat detector 100, the user can visually confirm the emission of light indicating the operation of the heat detector 100 from any direction, with the sensor 40 at the center, that the center of the heat detector 100 is emitting light.

[0085] As described above, in the first embodiment, the heat detector 100 includes the case body 10 having the opening 11 for housing the substrate 20 on which the sensor 40 for detecting heat and the light source 50 are mounted, and the case lid 30 provided below the case body 10 and made of a light-transmitting member that transmits the light of the light source 50. The heat detector 100 also includes a top plate 64 located below the case lid 30, and a protector 60 provided on the top plate 64 and having a protective portion 61 for protecting the sensor 40. The case lid 30 has a hole (first hole 31) through which the sensor 40 is inserted, and the hole includes a cylindrical portion 32 extending downward. The top plate 64 is provided with a top plate opening 64a in which the cylindrical portion 32 is disposed, and the cylindrical portion 32 is formed at a height H that is flush with the lower surface 64s2 of the top plate 64.

[0086] As a result, the cylindrical portion 32 in the hole (first hole 31) of the case lid 30 made of a light-transmitting member is disposed in the top plate opening 64a of the top plate 64 and becomes flush with the lower surface 64s2 of the top plate 64. Therefore, at the top plate opening 64a of the top plate 64, the wall constituting the hole of the case lid 30 transmits light from the light source 50, making the light easier to see.

[0087] Moreover, the hole (first hole 31) has a cone-shaped portion 33 whose opening width gradually increases downward, and includes the above-mentioned tubular portion 32 extending downward from the lower end of the cone-shaped portion 33. Moreover, the case lid 30 has a frame portion 34 extending from the lower end 33b of the cone-shaped portion 33 toward the outer periphery. This allows the light emitted from the light source 50 to be diffused in the cone-shaped portion 33 of the first hole 31, and increases the surface area of ​​the side from which the light is emitted in the first hole 31, making the heat detector 100 even easier to view when viewed from the side (front, back, left, or right).

[0088] In addition, a first step 32p is provided on the outer peripheral surface 32o of the cylindrical portion 32, the outer diameter of which increases on the upper side, i.e., the frame portion 34 side, and a second step 64r facing the first step 32p is provided on the upper surface of the top plate 64. This makes it easy to align the case lid 30 and the protector 60. In addition, the internal space of the case body 10 is less visible to the user, improving the design.

[0089] In addition, the case lid 30 has a plurality of legs 35 extending upward so as to fit along the inner surface of the case body 10. This allows the plurality of legs 35 to function as guides when attaching the case lid 30 to the case body 10, making attachment easy.

[0090] Moreover, one end of the wiring 27 drawn out to the outside is connected to the substrate 20, and a cutout portion (second cutout portion 16) in which the wiring 27 is disposed is formed on the edge of the opening 11 of the case body 10. Also, a cutout 23 is formed on the edge of the substrate 20, and a protrusion (guide protrusion 13) disposed in the cutout 23 of the substrate 20 is provided on the inner wall of the case body 10 so as to extend in the vertical direction. Thus, by providing the cutout portion (second cutout portion 16) in the case body 10, the movement of the wiring 27 can be suppressed, and when the substrate 20 is housed in the case body 10, the protrusion (guide protrusion 13) of the case body 10 serves as a guide for the substrate 20, making it easier to assemble the case body 10 and the substrate 20. As a result, this leads to improved ease of assembly.

[0091] Further, a pair of hooks 65c and 65d are provided on the top plate 64 of the protector 60, which extend upward and have folded-back portions 65c1 and 65d1 at their tips that face outward from each other. The interior angle θ2 of the folded-back portions 65c1 and 65d1 is an acute angle, and the case body 10 is formed with hook holes 14c and 14d into which the pair of hooks 65c and 65d fit, respectively. As a result, the pair of hooks 65c and 65d fit into the edges of the hook holes 14c and 14d of the case body 10, so that the protector 60 and the case body 10 are prevented from coming off after assembly.

[0092] The embodiment of the present disclosure is not limited to the above embodiment, and various modifications can be made. For example, the shape of the case outer shell 12 is not limited to the above, and may be, for example, a cylindrical shape having an upper surface. For example, the case where the entire case lid 30 is made of a light-transmitting material has been described, but only the first hole portion 31 in the case lid 30 may be made of a light-transmitting material, and the portion of the case lid 30 other than the first hole portion 31 may be made of a non-light-transmitting material. In addition, the second hole portion 69 is configured by the protective plate opening 62o and the gap 63g, but is not limited thereto, and may be configured by only the protective plate opening 62o or by only the gap 63g. The heat detector 100 described above can also be installed on the side wall of a room. In this case, the heat detector 100 is installed on the side wall so that the light emission side of the first hole portion 31, i.e., the protector 60 side, is exposed to the room. [Explanation of symbols]

[0093] 10 case body, 11 opening, 12 case outer shell, 13 guide projection, 14a, 14b, 14c, 14d hook hole, 14e claw hole, 15 first notch, 16 second notch, 17 positioning protrusion, 20 board, 21 bottom surface, 23 notch, 26 wiring connection portion, 27 wiring, 30 case lid, 31 first hole portion, 31a upper end surface, 31b lower end, 32 cylindrical portion, 32o outer peripheral surface, 32p first step portion, 33 bowl-shaped portion, 33b lower end, 34 frame portion, 34c groove, 34p lid projection portion, 34x claw portion, 35 leg portion, 40 sensor, 41 heat-sensing portion, 42 lead portion, 43 connection portion, 44 sensor base portion, 50 light source, 51 Light-emitting surface, 60 protector, 61 protective portion, 62 protective plate, 62o protective plate opening, 63 support, 63g gap, 64 top plate, 64a top plate opening, 64r second step portion, 64s1 upper surface, 64s2 lower surface, 65a, 65b, 65c, 65d hook, 65a1, 65b1, 65c1, 65d1 folded portion, 66 positioning recess, 67 spring, 69 second hole portion, 100 heat detector, 200 ceiling, 201 ceiling surface, 202 recess, D32a outer diameter, D32b outer diameter, Di32 opening width, Di0 minimum opening width, Di1 opening width, Di2a opening width, Di2b opening width, Do1 outer diameter, Do2 outer diameter, Do3 outer diameter, Ds depth, H height, K distance, SP circulation space, T thickness, θ1 interior angle, θ2 interior angle.

Claims

1. a case body having an opening for housing a substrate on which a heat sensor and a light source are mounted; a case lid provided below the case body and made of a light-transmitting member that transmits light from the light source; a protector including a top plate located below the case lid and a protective portion provided on the top plate for protecting the sensor; A heat detector comprising: the case lid has a hole through which the sensor is inserted, the hole having a cylindrical portion extending downward; The top plate has a top plate opening in which the cylindrical portion is disposed, The cylindrical portion is formed at a height that is flush with the lower surface of the top plate. heat detector.

2. the hole has a mortar-shaped portion whose opening width gradually increases downward, and the cylindrical portion extends downward from a lower end of the mortar-shaped portion, The case lid has a frame portion extending from a lower end of the mortar-shaped portion toward an outer periphery. The heat detector according to claim 1.

3. a first step portion having an outer diameter larger on an upper side of the outer circumferential surface of the cylindrical portion; A second step portion is provided on the upper surface of the top plate, the second step portion being opposed to the first step portion. A heat detector according to claim 1 or 2.

4. The case lid has a plurality of legs extending upward along the inner surface of the case body. A heat detector according to any one of claims 1 to 3.

5. One end of a wiring that is led out to the outside is connected to the substrate, a cutout portion in which the wiring is disposed is formed on an edge of the opening of the case body, The substrate has a notch formed at an edge thereof, A protrusion is provided on an inner wall of the case body so as to extend in the vertical direction and to be placed in the notch of the board. A heat detector according to any one of claims 1 to 4.

6. The top plate of the protector is provided with a pair of hooks extending upward and having folded portions at their tips that face outward from each other, and the inner angles of the folded portions are acute angles; The case body is formed with holes into which the pair of hooks fit. A heat detector according to any one of claims 1 to 5.

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